Sort out several important Android knowledge and advanced Android development interview questions

Preface

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Two 、Android Interview questions

Android The interview questions include Android Basics , There are also some source level 、 Principles, etc . So I want to go to a big company for an interview , Be sure to look at the source code and Implementation , Common frameworks can try their own handwriting to achieve , Exercise yourself .

（ One ）Android Basic knowledge points

• What are the four components

• The life cycle and simple usage of the four components

• Activity The way of communication between

• Activity Life cycle in all cases

• When the horizontal and vertical screens are switched ,Activity  Life cycle in all cases

• Activity And Fragment Life cycle comparison between

• Activity There are Dialog When you press Home The life cycle of the bond

• Two Activity  Which methods will be executed when jumping between ？

• Switch from the front to the back , And then back to the front desk ,Activity Lifecycle callback methods . eject Dialog, Lifecycle callback method .

• Activity Comparison of four startup modes of

• Activity The state is preserved in recovery

• fragment Life cycle in all cases

• Fragment State of preservation startActivityForResult What kind of method is it , Under what circumstances ？

• How to achieve Fragment The slide of ？

• fragment How to transfer data between ？

• Activity  How and Service  binding ？

• How the Activity  Start the corresponding Service？

• service and activity How to interact data ？

• Service How to open it

• Please describe Service  Life cycle of

• Talk to you about ContentProvider The understanding of the

• say something ContentProvider、ContentResolver、ContentObserver  The relationship between

• Please describe the broadcast BroadcastReceiver The understanding of the

• Classification of broadcasting

• The way the broadcast is used and the scene

• stay manifest  And how to register and use BroadcastReceiver?

• What's the difference between local broadcasting and global broadcasting ？

• BroadcastReceiver,LocalBroadcastReceiver  difference

• AlertDialog,popupWindow,Activity difference

• Application  and  Activity  Of  Context  The difference between objects

• Android Property animation features

• How to import an external database ?

• LinearLayout、RelativeLayout、FrameLayout The characteristics and comparison of , And introduce the usage scenarios .

• Talk about the understanding of interface and callback

• The principle of callback

• Write a callback demo

• introduce SurfView

• RecycleView Use

• The function of serialization , as well as Android The difference between the two serialization

• Differentiator

• Estimator

• Android How to store data in

（ Two ）Android Source code correlation analysis

• Android Animation framework implementation principle

• Android Versions API The difference between

• Requestlayout,onlayout,onDraw,DrawChild Differences and connections

• invalidate and postInvalidate The difference and use of

• Activity-Window-View The difference between the three

• Talk about right Volley The understanding of the

• How to optimize customization View

• Low version SDK How to implement higher version api？

• Describe the flow of a network request

• HttpUrlConnection  and  okhttp Relationship

• Bitmap Understanding of the object

• looper framework

• ActivityThread,AMS,WMS How it works

• Customize View How to consider model adaptation

• Customize View Events

• AstncTask+HttpClient  And  AsyncHttpClient What's the difference? ？

• LaunchMode Application scenarios

• AsyncTask  How to use ?

• SpareArray principle

• Please introduce ContentProvider  How to realize data sharing ？

• AndroidService And Activity There are several ways to communicate with each other

• IntentService What are the principles and functions of ？

• say something Activity、Intent、Service  What's the relationship

• ApplicationContext and ActivityContext The difference between

• SP Is it process synchronization ? What's the way to synchronize ？

• On Multithreading in Android The use of

• The process and  Application  Life cycle of

• encapsulation View How do you know view Size

• RecycleView principle

• AndroidManifest The role and understanding of

（ 3、 ... and ） Some common principle problems

• Handler Mechanism and underlying implementation

• Handler、Thread and HandlerThread The difference between

• handler Send message to child thread ,looper How to start ？

• About Handler, anywhere new Handler  Under what thread ?

• ThreadLocal principle , Implementation and how to guarantee Local attribute ？

• Please explain in the single thread model Message、Handler、Message Queue、Looper The relationship between

• Please describe View Event delivery and distribution mechanism

• Touch Event delivery process

• In event distribution onTouch  and onTouchEvent  What's the difference? , How to use ？

• View and ViewGroup There are callback methods related to event distribution

• View Refresh mechanism

• View Drawing process

• Principle of custom control

• Customize View How to provide access to View Interface to properties ？

• Android In the code WAP The Internet

• AsyncTask Mechanism

• AsyncTask Principles and shortcomings

• How to cancel AsyncTask？

• Why can't I update in a child thread UI？

• ANR What is the cause of this ？

• ANR Positioning and correction

• oom What is it? ？

• What causes oom？

• What is the solution to avoid OOM？

• Oom  Whether it can be or not? try catch？ Why? ？

• What is a memory leak ？

• What causes a memory leak ？

• How to prevent thread memory leakage ？

• Solution to memory leak field

• The difference between memory leak and memory overflow ？

• LruCache Default cache size

• ContentProvider Authority management ( answer ： Read / write separation , Access control - Accurate to the table level ,URL control )

• How to intercept and abort A text message ？

• Whether the broadcast can request the network ？

• Broadcast induced anr What's the time limit of ？

• Calculate a view Nesting level of

• Activity Stack

• Android There is no upper limit for threads ？

• There is no upper limit on thread pool ？

• ListView What is reused ？

• Android Why introduce Parcelable？

• Have you tried to simplify Parcelable Use ？

（ Four ） Some common problems in development

• ListView  How is the problem of image dislocation in Chinese ?

• Do you understand hybrid development ？

• Know what hybrid development methods ？ Tell their advantages and disadvantages and their respective use scenarios ？（ answer ： such as :RN,weex,H5, Applet ,WPA etc. . do Android Understand some front-end js It's good to wait );

• What are the processing skills of screen adaptation ?

• The server only provides data receiving interface , In the case of multithreading or multiprocessing , How to ensure the orderly arrival of data ？

• Understanding of dynamic layout

• How to remove duplicate code ？

• Draw  Android  The general structure of

• Recycleview and ListView The difference between

• ListView The principle and solution of image loading disorder

• Dynamic permission adaptation scheme , The concept of permission group

• Android Why is the system designed ContentProvider？

• Does the drop-down status bar affect activity Life cycle of

• If in onStop When I made a network request ,onResume How to recover when ？

• Bitmap  What to pay attention to when using ？

• Bitmap Of recycler()

• Android The main steps to turn on the camera in

• ViewPager Use details , How to set to initialize only the current Fragment, The others are not initialized ？

• Click event is blocked , But I want to pass it down View, How to operate ？

• Implementation of wechat homepage

• The principle of small red dots on wechat

• CAS Introduce （ This is Alibaba's interview question , I don't know very well , You can refer to the blog : CAS brief introduction ）

attach ;AndroidAPP Outline of development framework technology system ;

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The end of the

For many primary and intermediate Android For Engineers , Want to improve skills , Often is oneself gropes for growth , Unsystematic learning is inefficient, long and helpless .  I hope that these architecture technologies can be applied to Android Development of friends have reference and less detours , The point of this article is whether you have gained and grown up , The rest is unimportant , I hope readers will keep this in mind .

Finally, we want to get a high salary to improve technology and get a qualitative leap in salary . The quickest way , That is, someone can take you with them to analyze , This is the most efficient way to learn , So in order to advance to the middle and senior level smoothly 、 Architects , I specially prepared a set of master learning source code and framework videos for you Android Architect tutorial , Make sure you learn to make sure your salary goes up to a higher level .

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• When you have a learning path , What to learn , I also know how to go in the future , If you see too much theory, you have to practice it .